<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div {
            position: relative;
            width: 150px;
            border: 1px solid black;
            text-align: center;
        }

        ul {
            padding: 0;
            list-style: none;
            width: 150px;
            position: absolute;
            display: none;
            top: 5px;
        }

        div:hover ul {
            display: block;
        }

        li:hover {
            background-color: cornflowerblue;
            color: white;
        }
    </style>
</head>

<body>
    <div>
        卖家中心
        <ul>
            <li>免费开店</li>
            <li>已卖出的宝贝</li>
            <li>出售中的宝贝</li>
            <!-- <li></li> -->
        </ul>
    </div>
</body>

</html>